Re: [PATCH 0/5] Introduce 'yank' oob qmp command to recover from hanging qemu

[Lukas Straub]

On Mon, 11 May 2020 16:46:45 +0100
"Dr. David Alan Gilbert" <address@hidden> wrote:

> * Daniel P. Berrangé (address@hidden) wrote: 
> > ...
> > That way if QEMU does get stuck, you can start by tearing down the
> > least distruptive channel. eg try tearing down the migration connection
> > first (which shouldn't negatively impact the guest), and only if that
> > doesn't work then, move on to tear down the NBD connection (which risks
> > data loss)  
> 
> I wonder if a different way would be to make all network connections
> register with yank, but then make yank take a list of connections to
> shutdown(2).

Good Idea. We could name the connections (/yank callbacks) in the form 
"nbd:<node-name>", "chardev:<chardev-name>" and "migration" (and add 
"netdev:...", etc. in the future). Then make yank take a list of connection 
names as you suggest and silently ignore connections that don't exist. And 
maybe even add a 'query-yank' oob command returning a list of registered 
connections so the management application can do pattern matching if it wants.

Comments?

Regards,
Lukas Straub

> Dave
> 
> > Regards,
> > Daniel
> > -- 
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> --
> Dr. David Alan Gilbert / address@hidden / Manchester, UK
>

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